An internal combustion engine generally employs a fuel delivery system for delivering pressurized fuel into one or more cylinders thereof for combustion purposes. The fuel delivery system may include a fuel rail for storing and delivering the pressurized fuel into the cylinders. In order to limit over pressurization of the fuel rail, a pressure relief valve may be provided thereon to relieve excess pressure therefrom and, thus, limit damage to the fuel rail.
In many situations, the pressure relief valve may be mechanically operated. As a result, it may be difficult to detect an open event of the pressure relief valve. As the pressure relief valve may open, the pressure within the fuel rail may drop drastically resulting in undesired reduced performance of the engine. In some situations, opening of the pressure relief valve for an extended period of time may lead to premature erosion of components of the pressure relief valve, such as a valve element, seals, and so on. This may, in turn, lead to inaccurate operation, reduced safety of the fuel rail, reduced life of the pressure relief valve, increased replacement/service cost, and so on.
In some situations, opening of the pressure relief valve for the extended period of time may result in over working of the components of the fuel delivery system, such as a fuel pump. Over working of the fuel pump may increase a parasitic load on the engine, reduce fuel efficiency, reduce engine efficiency, and so on. Also, over working of the components of the fuel delivery system may further result in premature damage to the fuel delivery system, in turn, resulting in increased system cost, operational cost, machine downtime, service cost, labor cost, and so on. Hence, there is a need for an improved fuel delivery system.
U.S. Pat. No. 9,394,845 descries a first computer-implemented diagnostic method adapted to operate in response to an imminent deceleration fuel cutoff (DFCO) event. A second computer-implemented diagnostic method is adapted to operate during an engine shutdown. Both diagnostic methods are configured to control fuel injectors and a fuel pump in order to change a fuel rail pressure from a desired minimum to a desired maximum. Measurements from a fuel rail pressure sensor at these endpoints is then used in order to detect a fault of the fuel rail pressure sensor.